The invention relates to a piercing means protective device for a syringe having a syringe body and a piercing means arranged at the distal end of the syringe body, comprising a dimensionally stable sleeve element, which extends along an axial direction and at least partially encloses an inner element extending along an axial direction, wherein the inner element consists of a resilient material and at least partially encloses the piercing means.
Piercing means protective devices of this kind are normally used on prefilled syringes. The handling of such syringes is very simple, as the medium does not have to be transferred to the syringe prior to application. For vaccines and countless other medicines they are now the first-choice primary packaging material. These syringes are usually manufactured from glass or plastics material (for example COC, COP) and are equipped with a piercing means. Such piercing means, for example cannulas, normally have a very finely polished portion to permit an injection that is as pain-free as possible. Polished portions of this kind can easily be damaged by mechanical influences, as a result of which the patient may be caused unnecessary pain during an injection. The piercing means are therefore provided with a protective cap made of a resilient material. Such a flexible needle shield (FNS) protects the finely polished portion of the piercing means from mechanical influences due to its resilient properties. Furthermore, the sterility of the piercing means should be ensured. To this end, the FNS also encompasses the conical end piece of the syringe body. The piercing means is hermetically sealed by the seat of the inner element on the end piece of the syringe body, thereby ensuring the sterility of the piercing means.
However, due to its resilient properties, an FNS of this kind does not offer adequate protection from greater mechanical loads. Dimensionally stable sleeve elements were accordingly already arranged on the FNS. Such a system, consisting of a dimensionally stable sleeve element and a flexible needle shield (FNS), is also termed a rigid needle shield (RNS). The connection between the FNS and the RNS poses a problem here. In conventional piercing means protective devices, the FNS is held in a receptacle of the sleeve element. The resilient element frequently slips out of the receptacle and as result becomes separated from the dimensionally stable sleeve element. The dimensionally stable sleeve element could be lost in this case, giving rise to the risk of the piercing means being damaged. In addition, without any enclosing stable component, the FNS may be punctured and thus poses a risk in respect of needlestick injuries to the user.